ReadonlyfrontReadonlyhitReadonlyinstanceOptional ReadonlymaterialCompared when given: the hit's material index (NO_MATERIAL for none).
Optional ReadonlynormalCompared when given: the world-space geometric normal of the authored front side (unit).
ReadonlytReadonlytriangleReadonlyuReadonlyv
What a tracer returned for one ray.
t < 0orhit: falsemeans a miss.